In 1976, the United States Environmental Protection Agency (EPA) promulgated interim drinking water standards under the Safe Drinking Water Act (SDWA). In 1991, the EPA proposed revisions to the 1976 requirements, and in 1996 the SDWA was amended. The amended SDWA established a list of contaminants to be regulated under primary standards and secondary standards. The primary standards are based on health effects and the secondary standards are based on aesthetics. The standards establish a maximum contaminant level for several contaminants.
One group of contaminants that is regulated under the SDWA is called radionuclides, including radium, gross alpha, and uranium. The primary standards for these three radionuclides are 5 pCi/L, 15 pCi/L and 30 pCi/L, respectively. Other contaminants that are generally undesirable include arsenic, iron, and others. It can be appreciated that it would be desirable to have a method for reducing the level of contaminants in water that is withdrawn from a water well.
Similar to water wells, oil coming from oil wells can be contaminated. For example, oil contaminants can include sand, paraffin, water, or minerals. While contamination of oil is not typically a health hazard, the value and usefulness of contaminated oil is typically significantly less than that of cleaner oil. Therefore, it can be appreciated that it would be desirable to have a method for reducing the level of contaminants in oil that is withdrawn from an oil well.